The gas and electricity supplier npower today withdrew its cheapest online dual fuel tariff - the move was immediately hailed by analysts as further evidence that households across the UK can start planning for another round of price increases. Npower’s Sign Online 10 tariff had been the cheapest joint gas and electricity product in the market, and was aimed at customers switching supplier. The company’s new version of the same online tariff is around £83 a year more expensive than the one it replaced. With crude oil prices hovering around $120 a barrel - almost double the price of a year ago - wholesale gas and electricity prices have also been pushed upwards. Analysts have been predicting that domestic energy bills are set to rise between 10%, and a more likely, 25% over the next 12 months. Such a move would add another £180-190 to the standard average household bill, pushing it towards the £1,200 a year mark for the first time. “We don’t really talk about the online tariffs which can be withdrawn at any time,” said an npower spokesman. “There are no plans to increase the price for any of our other tariffs at the moment,” he said.